Articulated railway transportation system



United States Patent [54] ARTICULATED RAILWAY TRANSPORTATION SYSTEM 19 Claims, 8 Drawing Figs.

[52 u.s. c1. 104/246, 74/27, 1o4/94,104/1s1, 104/140, 105/4, 105/30, 105/59,105161,]05/96,105/1,105/l30,105/136,

151 1111.121. B61b5/00, B6lb13/02,B61f9/00 501 FleldofSearch 74/27,31;

104/94,13l,138,l40,146, 147; 105/4, 30, 59, 96,96.1,'l30.136,150, 153,155, 215; 188/264, 264A, 264AA, 2641; 192/41 [56] References Cited UNITED STATES PATENTS 131,839 10/1872 Baker 105/30X 132,586 1011872 Killam 105/155X 452,791 5/1891 .lackman 104/94 485,918 1111892 Ellis 105/215 905,370 12/1908 Roby 104/131X 1,112,979 10/1914 Castanho.. 105/155X 1,365,309 [[1921 Eaton 105/59 1,465,312 8/1923 Oyen 104/131X 1,701,013 2/1929 Ronk 105/153 2,584,190 2/1952 Danly et a1 188/264X 2,600,320 6/1952 Potter 105/59 3,244,116 4/1966 McGlade 105/96 3,352,254 11/1967 Lauber 105/4 3,366,203 1/1968 Dean 188/264(A) 3,384,031 5/1968 Dashew et a1. 104/140X 3,407,893 10/1968 Hill et a1. 192/41X 3,429,280 2/1969 Dashew et a1 l05/59X Primary Examiner- Arthur L. La Point Assistant Exam iner- Howard Beltran Attorney-Samuel Lindenberg and Arthur Freilich ABSTRACT: A train system including drive units for supporting and propelling material-holding modules. The drive units run on l-beam tracks and include drive wheels which roll on the top flanges of the l-beam tracks and two pairs of guide wheels bearing against the webs of the l-beams to align the drive wheels with the tracks. Each drive unit has a vertical kingpin coupling to the module behind it and a universal ball joint coupling to the module in front. The motor and brakes of each drive unit are cooled by a blower which draws air from the motor and blows it onto a ventilated brake disc. Each drive unit includes a gear drive which engages a rack along the rail at steep grades, the gear unit containing an overrunning clutch to enable engagement with the rack without accelerating the motor.

Patentgcl Nov. 17, 1970 3,540,380

Sheet 1 0:4

INVEN'IORS \STQNLEY A. DnsHEw g w STEPHEN TUMPAK MAZm-az Patented Nov. 17, 1970 3,540,380

Sheet 2 Of 4 g f INVENTORS [HI ,1 $TA-LEY A. .Dnsuaw I JOHN STEPHEN TUMPAK BY I I QTTOQAYE vs Patented Nov. 17, 1970 Sheet INVENTORS $7'0NLEV A, .D/QSHEMJ J'oHN STEPHEN 'T'u/wPnK HTTOQAYEVS Patented Nov. 17, 1970 Sheet IOO' BRAKE ENGAGE? INVENTORS STANLEV A. D QSHEW JOHN STEPHE TuMPnK Q1- To Q/JE VS ARTICULATED RAILWAY TRANSPORTATION SYSTEM BACKGROUND OF THE INVENTION This invention relates to rail transportation systems, and more particularly, to improvements therein.

The transportation of materials over distances on the order of several miles represents a major problem in many important industries. For example, the cost of transporting ore from a mine to a railroad, ship, or truck dock, represents a major factor in the cost of mining operations. The cost of such intermediate distance transportation is especially high when it is over rough terrain, and such costs may make uneconomical the exploitation of valuable minerals discovered in rough terrain.

Conveyor belts are extensively used for moving material, but they are often economical over only relatively short distances. For longer distances, such as several miles, conveyor belts become prohibitively expensive in many operations inasmuch as the cost increases almost proportionately with the distance. Furthermore, multiple conveyor belt systems, which are used where rough terrain with frequent changes of direction and slope are encountered, result in the requirement for many beltdriving mechanisms with attendant high construction and maintenance costs.

Automated railroad systems can be used to advantage over intermediate distances, inasmuch as practically the only machinery is contained in the moving vehicles, and increased rail lengths do not prohibitively increase costs or maintenance requirements. However,- to find wide use in material handling, such railroad systems must be operable at high speeds and over rough terrain wherein steep slopes are encountered. Furthermore, such systems should be capable of operation without a human operator on each train, and preferably without a requirement for a human operator to control train movements at the loading or unloading stations. Two copending U.S. Pat. applications, Bulk Transportation System by Dashew et al., Ser. No. 436,409, filed Feb. 15, 1965 and now U.S. Pat. No. 3,384,031, and Vehicle Propulsion System by Dashew et al., Ser. No. 539,421, filed Apr. 1, I966, and now U.S. Pat. No. 3,429,280, described a railroad system suitable for such automated operation. While the railroad systems described in these copending applications provide relatively economical intermediate distance material movement, any additional improvement to further lower costs would be highly desirable.

The railroad systems described in the foregoing copending applications utilize a train of cars which ride between two rails ofT cross section laid on their sides. The cars have weight supporting wheels riding on the leg of the T, and guide wheels bearing against the flange of the T. lt has been found that the leg of T-beam sections sometimes have irregularities which make it difficult to achieve smooth operation at high speeds such as 50 mph. Furthermore, the rails have to be supported at relatively close intervals.

The systems of the foregoing copending applications enable movement up steep slopes or even vertically up steep shafts (in which case the material carrying cars are covered) by utilizing a drive pinion which engages a rack on the rail for positive upward movement. The systems include a transition section of rail at points where the cars are required to slow down from high-speed traction wheel drive to a relatively slow rack-and-pinion drive speed, such as 4 mph. By the time the vehicle slows down and reaches the rack, the motor may be turning very slowly or may be stopped. If the motor drive has high inertia, large stresses may be placed on the pinion in accelerating the motor drive when the pinion encounters the rack. Improvements in these and other areas of such rail road transportation systems would be an important factor in lowering intermediate distance transportation costs.

OBJECTS AND SUMMARY OF THE INVENTION Accordingly, one object of the present invention is to provide a railroad-type transportation system for the automated transport of materials over intermediate distances.

Another object of the invention is to provide a railroad-type transportation system having a more economical and better utilized rail.

Still another object ofthe invention is to provide a railroad type transportation system utilizing a more efficient locomotion apparatus.

In one embodiment of the invention. a separate locomotive or drive'unit is utilized to pull and support each material-holding car, or module. The drive unit moves on two l-beam rails, and includes one pair of traction wheels resting on the flanges on the beams and two pairs of guide wheels, each pair ofguide wheels bearing against the web of the l-heam. Each pair of guide wheels orients a traction wheel so that it moves parallel to the length of the rail on which it is resting, thereby allowing free movement around curves. This overcomes the tendency of tandem wheels rigidly attached to the cars (as on railroad cars) to roll straight ahead on turns. Particularly where curves ofshort radius are involved, large amounts ofabrasive wear on the periphery of the traction wheel can occur which may represent a considerable maintenance and durability problem. This problem occurs in the standard trucks used on railroad cars, wherein flanges on the wheels are used to urge the truck around curves. In such trucks. both flange and rail wear oc curs, and considerable energy is lost in friction. ln the present invention, the drive unit precisely tracks around any curve so that its wheels are always aligned with the track, and no scuffing or resulting energy loses losses take place.

The use of an l-beam as a rail, with the traction wheels riding on the flange and the guide wheels rolling free against the web, provides a highly efficient rail system. As mentioned above, in the systems described in the foregoing copending applications, T-shaped rails layed on their sides where used with the traction wheels riding on the cantilevered leg of the T and the guide wheels bearing against the flange. Much of the stress was concentrated at the section where the cantilevered leg joined the flange. The l-beam rail provides a more efficient stress distribution.

In the present l-beam arrangement, the main vehicle load is carried by the wheels riding on the flanges at an area over the vertical web ofthe beam. The l-beam can resist bending forces very well in this configuration. and a light beam with relatively large spans between support points can be utilized. A further advantage of the l-beam arrangement is the fact that the beam flange is extremely stiff and straight by virtue of the centrally located deep web. This enables the flange to resist the development ofwaviness and humps in manufacturer or under the abuses encountered in handling construction and use. The smoother surface allows high speed travel with less shock and oscillations. The flanges are maintained most regular near the area where the web joins the flange. By positioning the traction wheels to roll on the flange near this smoothest area, smooth travel at high speeds such as 50 mph. is achieved.

The train of vehicles includes modules for holding materials to be transported and a two-traction wheel drive unit between each pair of modules for supporting one end of a module behind and one end ofa module in front. Pin joints could be used to connect the drive units to each of the modules, to allow flexibility around horizontal curves in the track. However, pin joints would not permit a train to move into or out of a steep incline. Ball joints could be used to permit the required flexibility at steep inclines, but they would allow the modules to pitch excessively. To provide the required flexibility and rigidity, each drive unit has a "pin joint connection to one module and a ball joint connection to the other module. so that each module has a pin joint at one end and a ball joint at the other. A pin joint at only one end is sufficient to prevent pitching, and a ball joint at only one end provides the necessary flexibility for movement into inclines and for banking.

Power to propel the vehicle at high speeds is applied through the traction wheels which also carry the weight. ln order to reduce stress and fatigue problems when heavy bend ing and torsional stresses are applied to a single cantilever shaft which supports and drives the traction wheels to coaxial shafts are used. The two shafts include an outer support shaft which transmits the weight of the vehicle to the traction wheels, and an inner drive shaft which transmits only torque for rotating the traction wheels. An end coupling connects the drive shaft to the outermost side ofthe support wheel. This arrangement enables the mounting of an idler wheel, which carries the vehicle during low-speed operations, on the support shaft inwardly ofthe traction wheel.

The vehicles are designed to run along the rails at high speed by means of smooth traction wheels, until an area is encountered where low-speed operation is necessary, such as at sharp inclines. At areas of low-speed operation, a gear pinion on the drive unit engages a rack on the rail for driving the vehicle. At steep inclines, for example, the rack-and-pinion drive carries the vehicle up a steep slope or prevents runaway down a steep slope. Transition between the highand lowspeed portions is attained by decnergizing the electric motors and applying breaking as required to allow the vehicle to slow down to a low speed before the pinion engages the rail rack. By the time such engagement occurs, the electric motor may have stopped. If the pinion were fixed to the motor drive, the pinion would have to quickly bring the motor up to the driving speed. For a motor drive of high inertia, this would impose a high load on the gear teeth of the rack and pinion. To reduce stresses on the teeth 'of the rack and pinion, an overrunning clutch is provided which disengages the motor drive from the pinion until the motor, when reenergized, attains the speed of the pinion.

While the overrunning clutch prevents excessive loads on the pinion, it allows the train to run away on steep downhill grades where the rack and pinion otherwise could slow the vehicle. To prevent runaways, a second pinion drive is provided which engages a rack along the rail after the pinion attached to the overrunning clutch is engaged and the motor has been brought up to full speed. By the time the second pinion is engaged, both pinions are moving at the same speed as the motor drives, and no overrunning clutch is required on the second pinion. The absence of the overrunning clutch allows the second pinion to slow the vehicle on downgrades and prevent runaways.

The driving unit is powered by electric motors which are cooled by forced air circulation. The unit also includes brakes which are preferably cooled. A cooling system is utilized which draws air through the motor housing and blows it onto a ventilated brake disc, so that both the motor and disc are cooled by a single blower system. Although the air which cools the brake disc is heated somewhat by passage through the motor housing, its temperature is sufficiently low to provide excellent cooling for a brake.

In the operation of a complete railway system, switching areas are generally required to take a train off the main track and allow another to move past. Instead of employing the usual horizontal switching arrangement, vertical switching is used. The siding for storing the train of vehicles is located above or below the main track, and a ramp is positioned to allow the train to move between the siding and main track. This allows the use of simpler switching apparatus and the saving ofspace.

The novel features of the invention are set forth with particularity in the appended claims. The invention will best be understood from the following description when read in conjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a transportation system constructed in accordance with the invention,

FIG. 2 is a plan view ofthe transportation system of FIG. I; FIG. 3 is a side elevation view ofa drive unit of the transportation system of FIG. 1;

FIG. 4 is a sectional end view taken on line 4-4 of FIG. 2; FIG. 5 is a detailed sectional view taken on line 5-5 of FIG.

FIG. 6 is a partial view ofanother embodiment of the invention which utilized a gear drive for preventing downhill runaways;

FIG. 7 is a partial schematic diagram of operating apparatus for the embodiment of FIG. 1; and

FIG. 8 is a side elevation view of a vertical switching ap paratus constructed in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 through 4 illustrate generally a rail transportation system constructed in accordance with the invention comprising a series of material-holding modules [0 and a support and drive unit 12 between modules and at the ends of the train. Each module 10 is supported by the two drive units at its ends. and each drive unit is generally supported by two traction wheels 14 which rest on the flanges 26 of l-heam rails to Each lbeam rail 16 is supported above the ground by columns l8 which are spaced along the length of the rail track. Each drive unit has two outriggers 20, each of which hold a pair of guide wheels 22. The guide wheels 22 bear against the webs 24 of the I-beams and maintain the traction wheels aligned with the rails even at sharp curves.

Each drive unit I2 is connected to the module 10 behind it by a pin joint 20 comprising a king pin 30 which projects through a pair of trunnions 32 on the drive unit and through pin-receiving holes at one end of the module. Each drive unit 12 is connected to the module in front of it by a ball joint 34 comprising a ball 36 fixed to the end of the forward module and a socket 38 on the drive unit.

The provision ofan articulated joint between the drive unit 12 and the module which it pulls markedly reduces wheel wear as the vehicles move around curves in the rail track. If

the traction wheel shafts were fixed to the ends ofthe module, then neither the front nor the rear traction wheels could be aligned with the rail on curves. The amount of abrasive wear on the periphery of the traction wheels would then be considerable, especially where curves are of short radius. Such wear could represent a severe maintenance and durability problem.

In the present invention, as noted above, the drive units are joined to the modules, to allow relative movement between them and each drive unit has only one pair of traction wheels. As a result, each drive unit can turn relative to the adjacent modules so that the pair of traction wheels is at all times aligned with the rails even as the vehicles moves around curves. The means for urging the drive unit to turn so as to achieve such alignment comprises the two pairs of guide wheels 22 on each drive unit. The guide wheels are mounted on outriggers 20, with one guide wheel in front of and the other in back of each traction wheel and bearing against the web of the rail. The guide wheels maintain the unit with the axis of the traction wheels directed along the radius of curtature ofthe rails, thereby preventing scuffing and energy losses. The outriggers 20 support the guide wheels in a manner which prevents lateral movement of the drive unit frame, so that the guide wheels constantly receive lateral forces from the rail webs to align the traction wheels with the rails. There are no other wheels supporting the drive unit excepting the traction wheels, which are located between the guide wheels. Accordingly, the drive unit can readily pivot to maintain each traction wheel in alignment.

The connections of each drive unit 12 to the modules [0 located behind and in front of it are designed to provide stability yet enable the degree of flexibility required to negotiate turns and move into and out of inclines. The pin joint 28 between each drive unit and the module it pulls provides pitching stability so that the module remains at all times essen tially parallel to the rails. Yet the pin joint provides the lateral flexibility necessary to enable two or more vehicles in a train to pass around a curve without binding. The ball joint 36, connecting each drive unit with the module ahead of it, provides not only lateral flexibility to enables the negotiation of horizontal curves, but vertical flexibility to enable a train of cars to move into or out of a steep incline. The ball joint also provides torsional flexibility about a longitudinal axis to enable banking or to allow a succession of cars to pass through a helical section of railway to turn over the ears in order to dump their loads. Turning over the cars is a method used for automatically unloading the train. lf torsional flexibility is not required, a universal joint which provides only lateral and vertical flexibility can be used, instead of one which also has torsional flexibility.

The last module in a train is attached to the wheeled unit behind it (which may not contain a motor) by a pin joint instead of a ball joint. The ball joint at the rear of each module is attached by bolts 37 which screw into threaded holes in the module, the bolts holding a bar 39 which carries the ball ofthe joint. The bolts 37 can readily be removed to replace the ball joint with a pinjoint for the last module in a train.

The use of the l-beam provides a rail with high strength under the loading conditions encountered in supporting the vehicles and enables smooth high-speed travel using ordinary beams as rails. The main vehicle load is carried by the traction wheels 14 which lie almost in the same plane as the vertical web of the l-beam. Thus, almost all bending forces applied to the rail between its supports is efficiently resisted by the web 24 of the l-beam and full utilization of the rail material is achieved.

The use of the l-beam arrangement provides a superior rail, not only because of the structural efficiencies involved, but because the portion of the flange directly above the web is generally smooth. During the manufacturer of handling of lbeams, the flanges may acquire a wavy or warped configuration. For vehicle travel at high speeds, such as 50 m.p.h. such undulations would lead to undesirable vehicle oscillations. it is found that the portionofthe flange where it meets the web has the smoothest configuration, and this smoothness is maintained over long periods of usage. Accordingly, ordinary lbeams can be utilized for high speed vehicle movements, thereby lowering the cost of construction and the maintenance ofthe system.

FIG. 5 is a detailed view of a drive unit, showing in detail, only the portion on one side ofa center line 50, the portion of the drive unit on the other side ofthe centerline being similarv The drive unit comprises a frame 52 on which is mounted two drive motors 54, each driving a separate motor shaft 56. A high-speed gear train connects the motor shaft assembly to a traction wheel 58, the traction wheel normally resting on the flange 26 of the rail 16 during high-speed movement of the drive unit along the rail. A low-speed gear train connects the motor shaft 56 to a drive pinion 64. The drive pinion 64 meshes with a rack 66 attached to the flange ofthe rail at locations where the vehicle must move at low speed, such as in movement up or down steep grades.

The high-speed gear train comprises a first pinion 68 fixed to the motor 56, the pinion and motor shaft supported on the frame by bearing 70 and another bearing (not shown). The

first pinion drives a second gear 74, which is fixed to a second gear shaft 76, supported on bearings 78 and 80. The second 4 gear 74 drives a third gear and pinion combination (not shown) mounted in a plane different from the plane 5-5 of FIG. 2. The third gear and pinion combination drives a fourth gear 82 which is fixed to a high-speed driveshaft 84 mounted on the frame by bearings 86 and 88. An outer end of the highspeed drive shaft 84 has a splined connection to an end drive fitting 90. The end fitting 90 engages a wheel. rim 92 on which the traction wheel 58 is mounted. Thus, as the drive motor 54 rotates, it drives the traction wheel 58 at a high speed. When the traction wheel is engaged with the flange 26 ofthe rail, the vehicle moves along the rail at a high speed, such as 50 m.p.h.

The low-speed gear train, which powers the drive pinion 64, includes the first pinion 68 and second gear 74 which cause rotation of the second gear shaft 76. A second pinion 94 fixed to the second gear shaft 76 drives a fifth gear 96 which is mounted on a fifth shaft 100 coaxial with the motor shaft assembly 56.'The fifth shaft is supported by a bearing 98 located between it and the motor shaft assembly 56, and by a bearing 102 positioned between it and the frame 52. The drive pinion 64 is mounted coaxially with the fifth gear shaft 100 and receives power therefrom through an overrunning clutch 104 disposed about the fifth gear shaft. When the vehicle is moving along those sections of track which contain a rack 66, the vehicle is driven by power supplied by the motor to the drive pinion 64 for movement along the rail at a relatively low speed such as 4 m.p.h. Sections of track which contain a rack 66 are generally placed only at areas where steep upgrades and downgrades are encountered and at loading and unloading docks, wherein high torque and/or low-speed movements are required.

in order to enable the vehicle to move up very steep grades and to enable them to be turned over as in unloading. an idler wheel 40 is provided which moves on the bottom flange 61 of the rail. A second idler wheel 106 is mounted coaxially with the traction wheel 58 for supporting the weight of the vehicle above the flange 26 when the traction wheel 58 for supporting the weight of the vehicle above the flange 26 when the traction wheel 58 is not engaged with the flange, as occurs during low-speed travel. An idler rail line 108 for supporting the second idler wheel 106 above the flange is positioned on the rail at such locations.

The traction wheel 58 and second idler wheel 106, only one of which supports the weight of the vehicle at any given time when it is upright, are not mounted on the high-speed drive shaft 84 but are instead mounted on a separate support shaft 110 which is hollow and which surrounds the high-speed drive shaft 84. The reason for the use of a separate support shaft 110. is to isolate the load of the vehicle from the highspeed shaft 84 which drives the traction wheel. Failure of shafts which drive and support wheels is often due to fatigue failure caused by the combination of bending and torsional loads in the same axle. Every time the axle rotates a half turn, the bending forces on the axle are reserved, that is, the shaft por tion which was in tension is now in compression and vice versa, leading to early fatigue failure unless very large axles are used. I

in the present invention, the traction wheel 58 is supported on a stationary shaft ll0 and yet driving power is transmitted to it even though the second idler wheel l06 is positioned between the traction wheel and the driving motor. This is accomplished by placing the high-speed driveshaft 84 within the stationary support shaft 110 and connecting the high-speed shaft to the traction wheel through the end drive fitting 90. The traction wheel 58 is rotatably mounted on the support shaft 110 by a pair of rollers bearings H2. and the idler wheel 106 is similarly supported on the support shaft by another pair of roller bearings 114. Neither the drive shaft 84 nor the support shaft 110 is subjected to reversals of loading. and con sequently relatively small shafts can be used.

The transition between highand low-speed low-specd operations is accomplished by locating the idler rail 108 and rack 66 at positions along the track wherein low-speed travel is desired. At high-speed sections of the track, the absence of an idler rail 108 and rack 66 results in traction wheel 58 carrying the entire weight of the vehicle and being engaged with the flange 26. At such times, the first idler wheel 40 is engaged with the bottom flange 61 by a moderate spring force which holds an idler wheel support axle (not shown) spring biased against the flange. At approaches to areas oflow-speed operation, an idler rail 108- is fastened to the upper flange 26, the height ofthe idler rail gradually increasing from nearly zero to an amount as shown in the figure which lifts the traction wheel 58 off the flange 26.

The raising of the traction wheel 58 off the flange 26 allows the vehicle to automatically slow down. Breaking may also be used to more rapidly decrease vehicle speed. When a suffcient distance has been traversed so that the vehicle has been slowed to a low speed, the rack 66 is encountered, and the drive pinion 64 engages the rack to positively move the vehicle along the rail. The second idler wheel [06 serves to hold the drive pinion 64 against the rack 66 so that positive engagement is assured. During such low-speed operation. the traction wheel 58 continues to rotate at a high speed, but its lack of, contact with the flange 26 effectively isolates its operation. This method of conversion from highspeed to low-speed operation eliminates the need for complex transmission clutches and for mechanisms to automatically engage and disengage them.

The use of the freewheeling or overrunning clutch 104 to connect the shaft 100 with the drive pinion 64 is an important factor in enabling smooth transition from high-speed to lowspeed operation without complex automatic transmission equipment. The overrunning clutch allows the drive pinion 64 to engage the rack 66 and be rapidly rotated by the rack, without requiring that the motor and lowspeed gear train be rapidly rotated. This is because clutch 104 allows the drive pinion 64 to disengage from the fifth shaft 100 when the pinion is moving faster than the shaft. The overrunning clutch 104 has rollers 126 caged inside a recess in the drive pinion. This recess is ofthe standard overrunning clutch configuration wherein torque applied by the inner shaft 100 causes the rollers to bind in an inclined ramp raceway so that driving torque is transferred from the shaft to the pinion.

The value of the overrunning clutch can be appreciated by considering the manner in which a transition from highto low-speed operation occurs. At a suitable distance before the vehicle enters a rack drive area, the vehicle is decelerated from its high speed by deenergizing the motor and applying braking until the vehicle is at a speed approximately equal to that desired for entering the rack drive zone. The vehicle is then lifted by the idler rails 108 so that the traction wheels clear the flange.

The deenergizing and braking can be accomplished by ineluding means along the track for automatically deenergizing the motor and applying the brake until the vehicle has reached the required low speed. FIG. 7 illustrates one example of such a system, comprising a pair of energizing rails 130 and 132 which carry current to power the drive motors 134. One rail 130 is always connected to the motor 134 and to a brake engaging mechanism 136. The other rail 132 is connected through the arm 138 ofa relay 140 to either the motor 134 or the brake energizer 136. A trip switch 142 is tripped by a projection (not shown) placed along the track at a location reached prior to the position where the vehicle enters the rack drive area. When the trip switch 142 passes by the projection, it trips the relay 140 so that it no longer delivers current to the motor 134 but instead delivers current to the brake engaging mechanism 136 which causes brakeshoes to bear against the brake disc and slow down the vehicle.

A speedometer 144 connected to the idler wheel 40 senses the speed of the vehicle. When the speed decreases to a predetermined value such as 4 mph, outputs from the speedometer trip another relay (not shown) in the brake-engaging mechanism to disengage the brakeshoes from the brake disc and allow the vehicle to coast. At a location after the beginning of the rack 66, another projection (not shown) placed along the track trips the switch 142 to reenergize the motor. Obviously, a large number of other systems can be used to deenergize a reenergize the motor and brake in the vehicle to bring it to the proper speed for entering the rack .drive area.

During most of the transition zone between high-speed and low-speed travel, the vehicle moves on the traction wheels 58. and only in the last few feet of travel is the vehicle raised on the idler rail 108. During the slowing down period, the motor slows down to such a low speed that the pinion 64 is almost stopped. In some cases the motor may be stopped entirely, since the fact that the vehicle has been raised on the idler rail 108 makes motor rotation and vehicle speed independent of each other. As the drive pinion 64 begins to mesh with the rack 66, the drive pinion must be quickly brought up to operating speed. Although the drive motor is subsequently reenergized, it may not be brought up to operating speed until the drive pinion 64 has moved some distance along the rack 66. If no overrunning clutch 104 were provided. the drive pinion 64 would have to quickly bring the drive motor and the gear train connecting the motor and drive pinion up to full operating speed as it becomes fully engaged with the rack. The motor and drive train have a high inertia. and attempts to accelerate them to full speed in a very short time might impose excessive stress on the drive pinion 64 and break its gear teeth. By providing the overrunning clutch, the only mechanism which must be rapidly brought to full speed is the drive pinion itself, which has a relatively low inertia. When power is ap plied to the drive motor, the initial motor torque is used to ac celerate the gear train. When the motor reaches the speed of the drive pinion 64, the overrunning clutch 104 engages, and the vehicle is smoothly maintained at its rack drive speed. the transition taking place with substantially no shock.

In some applications, long downhill grades may be encountered. Normally, a motor drive can be used to help brake the vehicle to prevent excessive speed, or runaway. However, the use of the overrunning clutch shown in FIG. 5 prevents the use of the drive motor as a downhill braking system. Instead, the overrunning clutch 104 allows the drive pinion 64 to rapidly accelerate without accelerating the motor. To prevent this, only some of the drive units are equipped with overrunning clutches, and the rest have a solid connection between the shaft and the drive pinion 64. Those units with a solid connection to couple the pinion to the motor maintain this coupling even on downhill grades, and allow the motor to serve as a brake.

In a train of many drive units and modules, there is typically a leading drive unit and second drive unit which each include an overrunning clutch to connect their drive pinions to their motors. Such units are shown in FIG. 5. The third and follow ing drive units include only solid connections between the drive pinion and motor. Such units are similar to the units of FIG. 5, except that there is no overrunning clutch I04. but only a solid connection. The power lines of all motors are connected together, so all motors are energized and deenergizcd at the same time. Alternating current is used to energize the motors, and all motors are of the synchronous type so they all turn at the same speed.

When the leading drive unit enters a rack drive area. its motor has not yet been reenergizcd. Synchronization of its pinion with the rack is accomplished by means disclosed in the foregoing copending patent applications. Such means com prise a length of rack with short teeth, the rack being springbiased toward the path of the drive pinion. Immediately after the pinion enters the rack area, all motors are rcencrgized. The motors generally reach full speed before the third drive unit reaches the rack drive area. When the motors reach full speed, the overrunning clutches in the first and second drive units become engaged and the motors drive the train. By the time the third unit reaches the rack drive area, the train is at or near full rack speed. Since the motors are also at full speed. the pinions of the third and additional units are easily synchronized to mesh with the rack.

FIG. 6 illustrates another embodiment of the invention which shown a drive unit similar to the one in FIG. 5, except that it includes a second. or auxiliary drive pinion ISO to prevent downhill runaways. The second drive pinion ISO is fixed to the same fifth gear shaft 100 which drives the first or primary drive pinion 64 through an overrunning clutch 104'. A second rack 152 is attached to the rail adjacent to the first rack 66. The beginning of the second rack 152 is at a point further along the track than the beginning ofthe first rack 66'. Accordingly. the second drive pinion begins to engage the second rack 152 only after the first drive pinion 64' is fully engaged with the first rack 66. Thus, the speed of the pinions 64 and 150 are the same when the second pinion engages its rack 152.

One difficulty which can arise in the use of the two pinions 104' and 150 is that they may be out of phase. This can arise because overrunning clutches are generally unpredictable as to the positions at which they engage. To obviate this difficul ty, the portion of the pinion within its rim 153 has a rubber core portion 151. The core portion 151 allows the rim 153 to rotate an angle equal to that ofhalf ofa gear tooth, relative to its shaft. A stop mechanism can be added to prevent more than a half-tooth rotation, where this is considered necessary. The use of an additional pinion 150 allows all drive units to be the same. With all drive units including an overrunning clutch 104, the motors for the units can be separately energized as each enters the rack area, and nonsynchronous motors can be readily used.

The cooling of the drive motor 54 is accomplished by a cooling fan 116 which is driven by a blower motor 118 which is separate from either of the drive motors 54. The air cooling arrangement is utilized also to cool a brake disc 120 which is engaged by a caliper shoe assembly (not shown) for slowing vehicle motion along the track. The brake disc 120 may operate at a relatively high temperature when it is in use. Accordingly, efficient brake cooling can be accomplished with air which has already been heated, so long as the temperature of the heated air is considerably below the relatively high temperature of the brake disc. Since the drive motor 54 operates normally at a much lower temperature than the brake disc 120, cooling of both can be performed efficiently with a single cooling fan. This is accomplished in the present invention by utilizing the air which cools the motor to thereafter cool the brake.

In the cooling system of FIG. 5, air is not blown into the motor casing, but instead the. cooling fan 116 produces a below-atmospheric pressure in the casing of the drive motor 54. Air is therefore drawn into the casing of the motor 54 to cool it, by passage through ports 122, this air then being exhausted from the motor casing by the fan 116. The air expelled through an exhaust 124 of the cooling fan is directed toward the central inlet area of the ventilated brake disc 120. The brake disc has radial holes through which the air passes to cool the brake material. While the ventilated brake disc can function without a blower, in that the rotation of the disc makes it act as a centrifugal fan, the cooling effectiveness is greatly enhanced by forcing air into the intake of the disc. Thus, by moving the same air through the motor and against the brake, an efficient cooling system is provided for the drive unit.

The switching of trains of vehicles is accomplished by a vertical switching apparatus illustrated in FIG. 8. The major portion 160 of the main track has a gap spanned by a rail section 162 which is pivotally mounted on the main track portion at 170. The rail section normally maintains a position in line with the rest of the main 'track to allow vehicles to pass therethrough. A siding 164, located directly above the main track, has a sufficient length to hold a train of vehicles. A ramp 166 pivotally mounted at one end 172 of the siding 164 can be lowered to the position shown at 166' to allow a train shown at 168 to move from the siding to the major portion of the main track. When the ramp is lowered, the pivoted rail section 162 of the main track is lowered to the position shown at 162'.

All of the rail sections, including the siding 164 and ramp 166 are constructed of l-beams. When the ramp 166 is lowered, the flanges of its rails align with the flanges of the major portion of the main track rails. The curved sections at each end of the ramp enable smooth rolling of vehicles and only limited pitching of the modules in moving off the siding and in moving onto the main track. A space is left between the ends of the ramp 166 and the ends ofthe siding and main track to which it connects to provide clearance for pivoting. Similarly, a space exists between the pivoted section 162 and the ends of the major portion of the main track which it contacts. The spaces are small enough to result in negligible shock when the traction wheels ride over them.

The vehicles to be stored on the siding 164 can be brought up from the main track either by backing them up the ramp or by providing a second ramp assembly similar to that shown in FIG. 8 to carry forward traveling trains up to the siding. Pistons 182 and 184 are used to move the free ends 174 and 176 of the pivoted section and rams, respectively. The pistons are attached to the rail flanges by brackets 178 and 180, and serve as means for moving the pivoted rail section and ramp up and down. The brackets are mounted on the outer sides of the flanges so that they do not interfere with the axles of the drive unit. The siding can, of course, be positioned below the main track, using a ramp apparatus similar to that described above.

Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art and consequently it is intended that the claims be in terpreted to cover such modifications and equivalents.

We claim:

1. A railway transportation system for moving vehicles along spaced rails comprising:

a bogie having a traction wheel on each side for rollably en gaging each of said rails;

a pair of guide wheels associated with each traction wheel,

one of the guide wheels of each pair being positioned before and the other of the guide wheels of each pair being positioned behind its associated traction wheel; and

means for supporting each pair ofguide wheels for engaging only the rail which its associated traction wheel rollably engages for preventing lateral movement of said bogie.

2. A railway system as defined in claim 1 wherein each of said rails has an l-beam shape with top and bottom flanges and a web connecting said flanges, said web being oriented in a generally vertical position, and wherein each said traction wheel is rollably engaged with the top flange of each of said pair of rails and each of said pair of guide wheels are rollably engaged with the web of the rail engaged by its associated traction wheel.

3. A railway system as defined in claim 2 wherein each said traction wheel has at least a portion thereof disposed against the area of the top flange directly above the intersection of the web and the top flange whereby a smooth trackway for supporting said traction wheels is provided.

4. A railway system as defined in claim 3 including a pair of idler wheels rotatably mounted on said bogie, and idler wheel being positioned against a rail bottom flange on a side opposite the web whereby to support said bogie on said rails even when said bogie is upside down.

5. A railway system comprising:

a pair of spaced rails;

a series of modules for holding items to be transported;

means for carrying said modules between said spaced rails including:

a bogie positioned between each adjacent pair of modules; each of said bogies having wheel means for I supporting the bogie on said pair of spaced rails, said wheel means including: A traction wheel rollably engaging each rail and a pair ofidler wheels associated with each traction wheel, each pair ofidler wheels rollably engaging the same rail as its associated traction wheel: pin joint means connecting each bogie to one module to which it is adjacent, for preventing relative pitching of the bogie and said module while allowing relative pivoting of the bogie and said module about a vertical axis; and universal joint means connecting each bogie to the other module to which it is adjacent for allowing relative pitching of the bogie and said other module in addition to pivoting between the bogie and said other module about a vertical axis.

6. A railway system as defined in claim 5 wherein said universal joint means comprises a ball joint means for additionally allowing relative rotation about a horizontal axis parallel to the length of the railway track.

7. A drive unit for a railway system having a pair of spaced rails comprising:

a bogie;

a pair of traction wheels for rollably supporting said bogie on said'spaced rails;

a pair ofguide wheels associated with each traction wheel of said pair and engaging the same rail as its associated traction wheel;

a support shaft means for each traction wheel mounted on said bogie, said support shaft means having a hole extending therethrough along its length;

said traction wheel being rotatably mounted on said support shaft means and having a first side facing said bogie and an opposite second side;

drive shaft means for transmitting power, said drive shaft means extending substantially through said hole in said support shaft means and having a first end located at said first side of said traction wheel and a second end located at said second side of said traction wheel;

motor means mounted on said bogie;

means for coupling said motor means to said first end of said drive shaft means; and

end fitting means coupling said second end of said drive shaft means to said second side of said traction wheel to drive said traction wheel.

8. A drive unit as defined in claim 7 including an idler wheel pivotally mounted on said support shaft means on said first side ofsaid traction wheel.

9. A railway system for carrying a train along a track at high speeds for some areas of track and at low speeds for other areas of track comprising:

motor means on said train including low-speed shaft means for providing wheel driving power at areas of low-speed travel;

first low-speed wheel means for moving said train at low speeds along said track;

overrunning clutch means coupling said lowspeed shaft means to said first low-speed wheel means for being disengaged approximately when said low-speed wheel means is rotating faster than said low-speed shaft means and for being engaged as said shaft means is rotating approximately as fast as said low-speed wheel means whereby to enable said low-speed wheel means to be rapidly ac eelerated without accelerating said motor means;

second low-speed wheel means for engagement with said track at steep downgrade areas thereof; and

means connecting said second low speed wheel means directly to said low-speed shaft means for transmitting power from said second low-speed wheel means to said motor means along steep down grades, whereby to prevent runaways.

10. A railway system as defined in claim 9 wherein:

said track includes first rack track means disposed near the beginning of steep down grades for engaging said first low-speed wheel means; and

second rack track means disposed forward of said first rack track means along said track for engaging said second low-speed wheel means whereby to allow acceleration of said low-speed shaft means to the speed of said first lowspeed wheel means before engagement of said second lowspeed wheel means with said track.

11. A railway system comprising:

a pair of spaced rails each having an l-beam cross section with top and bottom flanges and a web connecting said flanges;

a bogie having a pair of traction wheels for riding between said spaced rails, each of said traction wheels being engaged with the upper surface of the top flange of one of said rails for rolling therealong;

a pair of guide wheel means associated with each of said traction wheels; and I means connected to said bogie for rotatably supporting each of said pairs ofguide wheels means on either side of its associated traction wheel and against the inside web of the rail with which its associated traction wheel is engaged whereby to maintain each traction wheel aligned with the rail along which it rolls. 12. A railroad system as defined in claim It including:

a pair of idler wheels;

means for pivotally mounting each of said idler wheels on said bogie adjacent to each ofsaid traction wheels;

a pair of idler rails lines, each idler rail line mounted on one of said spaced rails along predetermined areas of low speed travel, to engage said idler wheels and lift said bogie sufficiently to clear said traction wheels from said top flanges;

rack means disposed along at least one of said rails at said areas of low-speed travel;

pinion means mounted on said unit for engagement with said rack means to drive said bogie along said areas of low-speed travel;

motor means mounted on said bogie;

means coupling said motor means to said traction wheels;

and

means coupling said motor means to said pinion means.

l3. A railroad system as defined in claim 12 wherein said means coupling said motor means to said pinion means includes overrunning clutch means for uncoupling said pinion means from said motor means when said pinion means tends to move faster in one direction than said motor means. whereby to enable rapid acceleration of said pinion means without corresponding acceleration of said motor means or said means coupling it to said pinion means.

14. A railroad system as defined in claim 13 including:

second pinion means for engagement with said rack means;

and

means connecting said motor means to said second pinion means for enabling the transmission of power from said second pinion means to said motor means during travel along steep downgrades.

15. A railroad system as defined in claim 11 including:

a pair of idler wheels, each idler wheel disposed coaxially with one of said traction wheels and between said pair of traction wheels;

idler rail line means disposed on said top flanges of said rails for engagement with said idler wheels to lift said bogie sufficiently to clear said traction wheels from said upper flanges;

support shaft means of hollow construction mounted on said bogie and projecting through a first of said idler wheels and at least partially through a first of said traction wheels for supporting said bogie on said first traction wheel;

first bearing means mounted on said support shaft means for pivotally supporting said first idler wheel means on said support shaft means;

second bearing means mounted on said support shaft means for pivotally supporting said first traction wheel on said support shaft means;

motor means mounted on said bogie for driving said first traction wheel;

drive shaft means coupled to said motor means and including a portion projecting through the hollow in said hollou support shaft means: and

end connecting means for coupling a portion of said drive shaft means projecting through said support shaft means to a side of said first traction wheel opposite said first idler wheel.

16. A railroad system as defined in claim 11 wherein said traction wheels are positioned on said bogie for movement 70 along the portion of said upper flange directly over said web whereby to provide smooth movement.

17. A railroad system as defined in claim 11 including:

a first module positioned behind said bogie having a first end portion adjacent to said bogie and a second end portion spaced remotely from said bogie;

means for supporting said second end of said module on said rails;

a second module positioned in front of said bogie. having a first end portion positioned adjacent to said bogie and a second end portion;

means for supporting said second end portion of said second module on said rails;

pin connecting means connecting said bogie to a first end portion of one of said modules for permitting pivoting between said bogie and said module substantially only about a vertical axis; and

joint means connecting said unit with the first end portion of the other of said modules for permitting relative pivoting between them about both vertical axis and a horizontal axis.

18. A railroad system comprising:

a first pair of spaced rails, each of l-beam cross section with top and bottom flanges and a web connecting said flanges;

a bogie having a pair of traction wheels, each of said traction wheel engaging with the upper surface of the top flange of one of said rails for rolling therealong;

a pair of guide wheel means associated with each of said traction wheels;

means connected to said bogie for rotatably supporting each of said pairs of guide wheel means on either side of its associated traction wheel and against the inside web of the one of the first pair of rails with the flange of which its traction wheel is engaged whereby to maintain each traction wheel aligned with the rail along which it rolls;

siding means having a second pair of spaced rails, said second pair of spaced rails being positioned substantially vertically with respect to said first pair of spaced rails;

ramp rail means having a first end pivotably connected to an end of said pair of second spaced rails and a second end;

means for selectively pivoting said ramp rail means to a first position wherein said second end is aligned with said first pair of spaced rails to permit the movement of a unit between said spaced rails and said siding means; and

a second position wherein said second end of said ramp means is positioned vertically from said first pair of spaced rails to permit movement of a bogie along said first pair ofspaced rails without interference.

19. A railroad system as defined in claim 18 wherein:

said first pair of spaced rails includes a major rail portion and a separate rail section. said section having first and second ends normally aligned with said major rail portion;

and including means for moving said separate rail section between a first position wherein said second end thereof is aligned with said major rail portion and a second position wherein said second end thereof is spaced from said major rail portion, to permit moving of said ramp rail means into alignment with said major rail portion;

and wherein said ramp rail means has top and bottom flanges; and

said means for selectively positioning said ramp rail means includes means for aligning said top and bottom flanges of said second end ofsaid ramp means with said top and bottom flanges of said pair of spaced rails of said major rail portion. 

